Citizen Scientists Aid Winter Fog Study with Mobile App

Fog Watch app developed by ICIMOD for the public to report fog during winter

Fog, a phenomenon that is common especially during cool weather, creates problems by affecting visibility, mobility, and reducing temperature significantly. It has adverse effects on agriculture, fisheries, and transportation. It even affects the health of people leading to loss of life and livelihoods. The episodes of prolonged dense fog persisting for several days in the Indo-Gangetic Plain (IGP) and Brahmaputra Basin have been increasing over the last two decades. This blanket of fog stretches across 1500 km, encompassing northeastern Pakistan, north India, Bangladesh, and the plains of Nepal and Bhutan. The exact reason for the increasing fog still remains a mystery.

The Atmosphere Initiative of the International Centre for Integrated Mountain Development (ICIMOD) along with other scientists in Pakistan, India, Bangladesh, Bhutan, and Nepal are carrying out a comprehensive interdisciplinary regional study in these countries. The research focuses on understanding the underlying causes, impacts and policy aspects related to this problem of persistent fog. One of the challenges in conducting research on fog across such a wide region is data scarcity. Visibility is monitored hourly at airports across the region, but little data exist in other locations. Satellite imagery can be mined to detect foggy periods but those images can be obscured by cloud cover at higher levels in the atmosphere.

GPS locations from where data were transmitted by Fog Watch app users to ICIMOD Server

To help fill this data gap, ICIMOD developed a mobile application – Fog Watch – to crowd-source geo-located and real-time data from residents across the above listed five countries.

The App was created in an easy, user friendly way that prompted two simple questions about the presence, and intensity of fog in the user’s current location based on visual observation. GPS was necessary for the App to determine location. The App had the provision of storing observation on the phone which could be uploaded when the user had internet access.

The App was intended to collect massive amounts of data on the presence and intensity of fog at various points in time and space across the IGP and Brahmaputra region. Using the App, participants collected observation data from 17 November 2015 through 02 March 2016. Simple, objective YES or NO questions were sent to users asking if fog was present at their current location. If the answer was ‘YES’, another question enquiring about the density of the fog would be sent. When the users responded, ICIMOD Server would record 5 pieces of information that included user id, response, time at which the prompt was sent and response received, and GPS location of the user.

Number of data points collected on fog and non-fog conditions throughout the winter

However, there were certain limitations of the App. Due to resource constraints, the App was feasible only for Android phones so the users of iPhones weren’t able to contribute. Despite a few technical glitches that were encountered, 2760 entries of data were registered by the end of the winter season. The highest number of entries, 1536, was received from India. Nepal and Pakistan followed with 689 and 559 entries, respectively.

To acknowledge and recognize dedication of people who installed the app and contributed to information gathering on a regular basis, 15 most active Fog Watch users were acknowledged as ‘Citizen Scientist’ and were presented printable certificates. The data compiled is expected to further understanding of persistent fog episodes.

Fog was most often reported during the morning hours of 5:00 – 9:00 and the evening hours from 5:00 – 8:00. Reports of fog dropped sharply during mid-day, which is consistent with our understanding of this weather phenomenon. ‘Fog Watch is a first-of-its-kind App introduced by ICIMOD to improve data collection for studying fog in the region,’ said Dr Prakash Bhave, Senior Air Quality Specialist at ICIMOD. He further added that the data collected by citizen scientists will be compared with surface observations at airports and with satellite imagery to assess the accuracy of the crowd-sourced data.

The information about Fog Watch was disseminated through email announcements and social media. Partners in respective countries also helped in promoting the app. Encouraged by the results of data collection last winter, researchers are considering ways to expand its user base in the next winter.